Conventionally, a mask for protecting the respiratory system is generally formed with a rectangular gauze which widely covers not only nostril openings, but also the mouth. The mask also includes a pair of elastic rings which are connected at opposite ends of the rectangular gauze and are configured to be wound around the ears. In the alternative, the mask is formed with the rectangular gauze, a rhomboid shaped cover and elastic rings which are connected to opposite ends of the cover and are configured to be wound around the ears.
A gas protection mask which is designed to be used during war or disaster covers a greater area of the wearer's face than a general purpose mask. Setting of such a mask on the face is done by tying both ends of the mask to the occipital region or, if the mask is designed as such, by placing a bag-like mask over the head.
In the normal course of life, there are many situations where it would be desirable to protect one's respiratory system from the external environment. For example, there are situations where it would be desirable to protect one's respiratory system from disease-causing bacteria, influenza viruses and the like, dust, flying anther dust, spraying chemicals, exhaust gas, the smoke from cigarettes, fumes resulting from painting, drying, low temperature and so forth, for maintaining the body in a healthy condition. However, the conventional mask covers not only one's nostrils, but also one's mouth, thereby covering the lower half of the face below the eyes. Therefore, the mask is generally too bulky to carry.
U.S. Pat. Nos. 4,004,584 and 5,392,773 disclose a breathing filter which includes a filter layer which covers only the nostril portion of the nose, and a support layer with adhesive material disposed at borders of the filter.
On the other hand, U.S. Pat. No. 4,984,302 discloses a nose-worn air filter which includes a filter element that covers the nostrils and base of the nose, and an adhesive strip which includes two triangular portions which are designed to adhere to the sides of the nose thereby holding the filter in place.
However, the masks disclosed in the above-identified patents are not designed such that they can generally correspond with various sizes and shapes of nostril openings. The line of junction between the base of a nose and the facial surface below the nose actually varies among different people. Nose height also varies from person to person. As a result of not being readily adjustable to correspond to such variables, these masks would have to be produced in numerous sizes and patterns, and could hardly be cost effective.